Live Electro-Optic Imaging of Microwave Near-Fields via Ultra-Parallel Photonic Heterodyne

We present the first demonstration of fine Live Electro-optic Imaging (LEI) of electrical signals on a microwave circuit. Patterns of their electric-near-fields are lively depicted on a display screen with a rate as high as 20 frames per second. In this system, a sensing light beam is modulated by an electro-optic (EO) crystal plate with the electric near-fields applied, and its spatial pattern of EO modulation are detected by a two-dimensional photo-detector array, where the frequency of modulation is down-converted by photonic heterodyne of large-scale parallelism. A digital signal processor (DSP) is employed to extract the frequency component of interest and to make it animated on the display screen. As examples, we present motion pictures of electric field pattern data acquired by the system in a real-time manner.